1. Field of the Invention
The present invention relates to an imaging apparatus, a signal processing method, and a program, and particularly relates to a signal processing technique concerning a multi-band image signal acquired by the imaging apparatus.
2. Description of the Related Art
A multi-band camera having more bands than the conventional three bands composed of red (R), green (G), and blue (B) is being developed to acquire spectral image data recording the spectrum of an object. For example, Japanese Patent Application Laid-Open No. 2003-87806 discusses configuration of a multi-band camera having color filters of six bands or more to acquire spectral data of an object.
However, the amount of data of spectral image data acquired by a multi-band camera becomes large. If, for example, the spectrum of an object of 400 nm to 700 nm is acquired and recorded in increments of 10 nm, it becomes necessary to use color information in 31 dimensions so that when compared with a conventional RGB 3-band camera, ten times or more the data storage capacity will be needed. Moreover, display devices capable of displaying such a spectral image are currently limited to special display devices. Most conventional display devices make a color display using three primary colors of R, G, and B. To generate image data displayable in such a conventional display device, it is necessary to convert a vast amount of spectral image data into image data of R, G, and B. Thus, processing in which real-time processing is demanded such as a preview of photographing results particularly by a multi-band camera and auto-focus (AF) processing using a photographed image cannot be performed in real time.